OFFICE OF THE PROV. March FOR MONTGOMERY COUNTY,

Rockville, June 15, 1863.

Colonel JAMES B. FRY,

Provost-Marshal-General:

DEAR SIR: I have just returned from the scene of the late rebel raid in Montgomery County, Md., and learned some facts which I think my duty to lay before the Government. The Chesapeake and Ohio Canal is almost wholly officered and worked by men having little or no sympathy for our Government.

I speak of the superintendents and lock-keepers on the line; two very important points on the canal (the locks at the Great Falls and the Seneca locks) are in the hands of our enemies. The population along the banks of the Potomac is disloyal. There is a ford at the head of Conn's Island, near the Great Falls. Suppose the rebels should cross at that point, what friend is at hand to give the alarm? It is true there is a company of cavalry stationed at the Falls, but with the aid of disloyal citizens who know every curve in the river, what chance would our pickets have to give the alarm? The lock-keeper at Seneca is disloyal, and the people in the neighborhood. The rebels came over, captured the pickets, and attacked the Federal cavalry stationed there. The orderly sergeant of that company, with his last words, said that a man by the name of Lewis Cross (who lives close to the camp) displayed signal lights to the rebels from his upper chamber, thus aiding them in their marauding expedition.

I also learned that the superintendent on the Washington Aqueduct, with all the hands employed under him, are utterly opposed to the Government. This force of worthies is stationed at the Great Falls, where they have an opportunity of watching the movements of our troops stationed there, and be ready at a moment's warning to act with the rebels in capturing or destroying them. The Potomac is very low at this time, and the bands of Mosby and White have a great many men with them from this county who know every foot of the river as well as every crossing.

I would most respectfully suggest that none but true and loyal men should be permitted to have any place of public appointment, and no rebel sympathizer should be permitted to enjoy his home who would welcome a band of cut-throats to destroy the defenders of the Government which protects him.

The rebel sympathizers in this community are worse than ever in their hatred to the Government, and they should be made to feel that no enemies can exist in the rear.

Respectfully, your obedient servant,

M. MOULDEN,

Provost-Marshal for Montgomery County.

P. S. - Is the Government aware that a letter could be thrown across the river at the Falls by wrapping it around a stone, thus giving the rebels a chance to learn our movements? And there are plenty of rebel sympathizers to do it.

M. M.

[JUNE 15, 1863.- For correspondence relating to raising troops in Massachusetts, see Stanton to Andrew; Andrew to Stanton, and Stanon to Andrew, Series I, Vol. XXVII, Part III, pp. 141-143.]

[JUNE 15, 1863.- For correspondence relating to raising troops in Michigan, see Blair to Stanton, Series I, Vol. XXVII, Part III, p. 144.]